Ovaries that's brilliant!! ENFP married to INTJ here too.
We're clearly the best type-couple 
It works because it's not particularly complicated BTW, it just looks like it.
Most people are happy to sit themselves on one side of a fence if presented with it and MBTI is basically just four fences:
Do you get energised by having company (E) or from alone time? (I)
(Most people know what introvert/extrovert are anyway by now since it's so trendy)
Are you more focused on the here and now (S) or on what's possible/what might happen? (N)
When you make decisions: are you a head person (T) or heart person? (F)
Are you more organised (J) or a scattered mess? (P)
So you go okay, I'm an ENFP - that means I'm a people-loving scattered mess who's always living in the clouds and makes decisions with her heart. DH (INTJ) is an introverted, logical person who has a plan for every conceivable possibility. [organised + possibility orientated]
It's not hocus pocus or astronomy, it's just feeding back exactly what you've told the machine. Then they make assumptions drawn from the combinations of these four traits which tend to be accurate enough because again they are based on the same information.
Ignore the titles though, they are a bit random and seem to change completely based on what site you're on. If the description you get isn't you then you might have one of your fences wrong. Make sure you're picking based on what you're actually like and not what you wish you were like - I have a tendency to think I'm a bit more head over heart but in reality when I make decisions day to day, I'm not.